City Nature Challenge 2020: Cape Town's Journal

May 04, 2020

Thank You Cape Town

Another City Nature Challenge under the belt.

Dallas Fort Worth put in a noble challenge at the end, and came within 700 observations of us. But, with America in bed, we remain top for number of observations with 34,147 observations.
Very well done Cape Town.

Our top species are: (see them here)
322 Portulacaria afra Common Spekboom
269 Apis mellifera Western Honey Bee
266 Afrogecko porphyreus Marbled Leaf-toed Gecko
258 Cornu aspersum Brown Garden Snail alien
246 Tecomaria capensis Cape Honeysuckle
211 Hibiscus rosa-sinensis Chinese Hibiscus
206 Crassula ovata Jade Stonecrop
199 Aloe arborescens Krantz Aloe
191 Strelitzia reginae Common Bird-of-paradise Flower
187 Cotyledon orbiculata Pig Ears
167 Streptopelia senegalensis Laughing Dove
166 Passer melanurus Cape Sparrow
163 Cinnyris chalybeus Southern Double-collared Sunbird
161 Streptopelia semitorquata Red-eyed Dove
146 Clivia miniata Natal Lily
143 Plumbago auriculata Blue Plumbago
143 Plectranthus neochilus Mosquito Bush
138 Zosterops virens Cape White-Eye
129 Lavandula dentata French Lavender
124 Bradypodion pumilum Cape Dwarf Chameleon
124 Osteospermum moniliferum Bietou
119 Schinus terebinthifolia Brazilian Pepper
116 Citrus × limon Lemon
112 Bostrychia hagedash Hadeda Ibis
112 Salvia rosmarinus Rosemary

Of these only nine are indigenous to Cape Town. The rest are aliens. Can you list them?
The dominance of garden plants is to be expected with lockdown and people tied to their gardens, and especially some of the species being very popular for attracting birds and butterflies to our gardens.

Our top observers (listed those with 200+ observations) are:
1 jeremygilmore 834
2 lmossop 558
3 juleswood 543
4 tonyrebelo 499
5 penny21 368
6 cpt_cj 364
7 charmaineoxtoby 314
8 thomasashworth 308
9 carinalochner 292
10 anthonyhitchcock 290
11 dangerranger 279
12 gigilaidler 275
13 eileenvh 268
14 michellethomson 264
15 louise95 260
16 hwittridge 258
17 photogenie 258
18 phyllida 254
19 andrewstephenmorton 251
20 diveinn_capetown 250
21 muonmo 232
22 petrobotha 220
23 kari_cousins 214
24 bonganimnisi 212
25 daryldbs 206
26 rion_c 204
27 melodibui22 202
28 teyounce 200

Again, due to the lockdown, no one got over 1000 observations (just how much can you do in a garden?). But several hundred observations from a garden is no mean achievement Thank you everyone. I trust that you now appreciate your garden and its wildlife like never before! And it is quite OK to continue recording from your garden on iNaturalist - please do!

The top recorders of species (more than 100 species from their gardens) are:
1 jeremygilmore 335
2 lmossop 294
3 anthonyhitchcock 237
4 juleswood 227
5 charmaineoxtoby 200
6 penny21 191
7 cpt_cj 184
8 carinalochner 177
9 photogenie 173
10 hwittridge 170
11 thomasashworth 159
12 muonmo 158
13 tonyrebelo 149
14 louise95 141
15 bonganimnisi 140
16 kari_cousins 140
17 petrobotha 132
18 eileenvh 129
19 diveinn_capetown 128
20 michellethomson 124
21 faylinder 120
22 teyounce 118
23 dangerranger 117
24 daryldbs 117
25 suley19 110
26 phyllida 108
27 melodibui22 107
28 liza81 102
29 louisvw 102

These results are little biased by a few observers who were able to get out - because they live on big estates, or were on patrol duty. However, there are some really amazing garden counts. Who would have guessed that many of our gardens have more than 10 species of butterflies (see them) present, and nearly as many bee (see them) and fly (see them) species. And I am certain that dozens of gardeners discovered their chameleons for the first time ever. Unfortunately our bees, flies and spiders (see them) have a very low identification rate: it appears that most cannot be identified below generic level, so we dont know our true species counts. Otherwise flies and bees would be in our top tally. I am sure that many people dipped out of species in their gardens (I missed Guinea Fowl, Carpenter Bee, Painted Lady, African Monarch, Leopard Toad, River Frog - see everything I dipped out on HERE - this compares the CNC2020 to past years for Mar-May in my garden) Note I added 109 new species to my garden in the CNC2020! - I am sure that you also discovered many new species in your garden!! Please dont stop recording them: why not make a garden project for your data (Hint: dont make a project, make a "Place" - but note you cannot hide your location if you decide to do this, so if privacy is a concern then this is not for you! - and iNat will not display species threatened by collecting! - at present this includes the Rainfrog and Golden Mole)

Many thanks to the tireless identifiers who worked solidly for a week helping identify our observations. These could be anywhere in the world, and indeed experts world-wide dipped in and helped out. We are especially grateful to them:
Here are those who made more than 400 identifications in Cape Town's lists:
1 jeremygilmore 8,024
2 tonyrebelo 4,816
3 rion_c 3,087
4 petrabroddle 2,648
5 alanhorstmann 2,431
6 venturefoth 1,458
7 rjpretor 1,307
8 fynbosphil 1,287
9 linkie 941
10 hvardaman 816
11 arboretum_amy 805
12 richardadcock 668
13 pieterwinter 655
14 dianastuder 602
15 colin25 586
16 alexiz 568
17 adamwelz 465
18 happyasacupcake 458
19 cheekychew 429
20 don_k 421
21 cliffdorse 402

Note that these totals do not include identifications on one's own observations: only those on other people's observations. So for many the total is a hundred or more additional identifications.

A few "did you knows"

  • Scouts contributed 24% of our observations! That is a magnificent effort! Many Thanks!!
    We hope that you will continue to help out for the rest of the year with monitoring the Polyphagous Shothole Borer Beetles in your neighbourhoods, as well as contributing to the Chameleon, Rainfrog and Ant Atlasses in Cape Town. Dont forget to add your "Scouts SA" project, and if you want your group and patrol names.

  • Garden Route has the second highest tally (after us, of course) of any city outside of the USA! Very well done guys!!

OK: now we sit and wait. The official results will be out later this afternoon.

With Lockdown a little more relaxed at Level 4, we can now go and monitor the Chameleons & PSHB in our neighbourhoods during "exercise time". Enjoy the fantastic weather, although perhaps it is time to start praying that we will get some rain?

Keep well and keep safe.
Your 2020 CNC organizing committee
(Aaniyah, Charmaine, Eleanor, Georgina, Ielhaam, Ismail, Julia, Kabelo, Kerry, Leighan, Megan, Natanya, Rupert, Sihle, Tony & Wendy)

Posted on May 04, 2020 08:39 by tonyrebelo tonyrebelo | 10 comments | Leave a comment

May 03, 2020

Identification of observations: Phase III

With 12 hours of identifications left for us it is time to move onto Phase III

There is still a little mopping up to be done from Phase 1 (Unidentified and Vaguely ID'd observations), but it is not really important at this stage.
No IDs yet - only make an ID if you recognize it - otherwise leave it without an ID. - 398 observations
Useless IDs (too vague) - can you make these finer? To family, genus or species?. - 353 observations

We also appear to have run out of steam on Phase 2 (Getting IDs down to species level).
This is probably because many of the observations remaining cannot be refined (e.g. some invertebrates, and among plants - for instance Bougainvillea where ID to hybrid parents is not trivial). But we can still make a serious dent in these - they amount to 34% of our observations. If you wish to tackle these, then please use this url, and add your tribe, family, or genus in the species box to access these.
IDs needing refined to species level - 11,633 observations

However, our main focus must now shift to Phase 3 (Research Grade). These are the observations that need to get to research grade. They have been identified, but these need to be checked and agreed to. With 3,968 observations, they amount to 10% of our data. Because they are so few we wont split them into groups - just add your taxon name (e.g. birds, Erica or spiders) to the species box to narrow your group.
IDs needing confirmation for Research Grade - 3,968

We probably wont have time for Phase IV (Checking), which is checking that
-a- all the Research Grade IDs to make sure that erroneous IDs (e.g. Californian species via the AI species recognition system) are done and
-b- all the Planted observations are marked as such.
The easiest way to check is to use this link, and to add your group.
Quick Check on species
If there are dubious species - they will hopefully be at the tail end of the list - you can see their observations by clicking on the text "observations" on the bottom of the picture card. This opens up a page showing the actual observations which you can then process by clicking on them.

If there are too many, in the filter box, click on the "Identify" option on the bottom of the filter box to open the Identify tool.

The end is near. The midnight deadline looms.
Thanks for a magnificent effort. An especial thanks to those who did so much: Please see them here and give them a round of applause as they finish off this task!

Posted on May 03, 2020 09:46 by tonyrebelo tonyrebelo | 3 comments | Leave a comment

April 30, 2020

Identification of observations: Phase II

We have now come to the end of Phase I. All the observations now have an identification at some level

Mopping up will continue. If you could help to get these down to the level at which our specialists can process them it will be appreciated.
No IDs yet - only make an ID if you recognize it - otherwise leave it without an ID. - 390
Useless IDs (too vague) - can you make these finer? To family, genus or species?. - - 470

But our main work now moves to getting identifications to the species level. This is the most formidable task, and needs to be done group for group.
If you know of any specialists who can help, please enlist them this weekend and send them the link.
Statistics for the groups will be provided in the comments, and links provided here with the current needs
Updated regularly! Last update -20:00-Sat. (in brackets Thursday 23:00) -
DEADLINE: midnight at end of 3 May 2020
((click to activate))

So, please choose your group:
Birds - 149 (204)
Mammals - 20 (27)
Herps - 22 (34)
Fish - 26 (26) ATTENTION

Molluscs - 98 (161) (includes marine ATTENTION)
Spiders - 672 (659) ATTENTION
Insects - 2,659 (2,675) {please add your group to refine search} ATTENTION

Fungi & Other:
Fungi (incl. Lichens) - 267 (235)
Other - 1 (1)

Plant Families: (with more than 50 IDs outstanding)
Stonecrops (Crassulaceae) - 759 (843)
Daisies (Asteraceae) - 620 (674)
Aloes (Asphodelaceae) - 610 (751) ATTENTION
Mints & Plectranthus (Lamiaceae) - 439 (489)
Asparagaceae (Yucca, Agave, Asparagus) - 314 (326)
Vygies (Aizoaceae - Mesembryanthemaceae) - 313 (327)

Lilies (Amaryllidaceae) - 204 (210)
Pelargonium (Geraniaceae) - 188 (203)
Bouganvilleas - 178 (139)
Bromeliads & Airplants - 177 (190)
Rosaceae (Roses) -167 (170)
Cacti (Cactaceae) - 148 (183)
Hibiscus (Malvaceae) - 134 (158)

Conifers (Pinopsidae) - 127 (131)
Grasses (Poaceae) - 123 (147)
Gums & Myrtles (Myrtaceae) - 111 (129)
Peas (Fabaceae) - 106 (114)
Proteaceae (Proteas) - 114 (175)
Cape Reeds (Restionaceae) - 109 (123)
Aroids (Araceae) - 103 (109)

Orchids -96 (100)
Sedges (Cyperaceae) - 91 (117)
Irises (Iridaceae) -90 (96)
Stapelias & Frangipangi (Apocynaceae) - 80 (106)
Tomatoes & Nightshades (Solanaceae) - 75 (93)
Mosses - 73 (69) ATTENTION
Palms - 68 (97)
Buchus & Lemons (Rutaceae) - 55 (78)

Use this and add your family to check your own special group:
add your family or genus

(Blackeye Susans) Acanthaceae - 15 (56)
Craneflowers - 7 (90)
Spekboom - 3 (151)

Posted on April 30, 2020 22:10 by tonyrebelo tonyrebelo | 12 comments | Leave a comment

April 29, 2020

Identification of observations: the process

OK: I trust that we are all doing our identifications! A great Lockdown activity.

Our strategy is simple:

Wednesday: clear the backlog of observations that have no identifications at all.
To do this please:

  1. Make IDs to "family level" in plants. Animals are not an issue (birds, reptiles, frogs, moths, bugs, butterflies, fish, spiders, etc. are all easy enough). And fungi are too diffcult: just please use Fungi, except for Lichens: these should be Lecanoromycetes (just type Lichens and choose this). But for plants, please try and get the families. These should be easy for flowers for Daisies, Peas, Proteas, Vygies, Stonecrops, Aloes (Asphodelaceae), Orchids (we wish), grasses, irids and other iconic groups. Ferns and Mosses are OK "families" as well. If you dont know the family or genus, then just skip it: Do NOT ID them as "Plants" or "Dicots" unless there is no chance that they will ever be identified.
  2. Other tasks to do while doing this:
  3. 2a: look out for superb photographs, outstanding observations and really cool stuff: - for these add the project "Nominations for Observation of the Month".
  4. 2b: Planted stuff - if something is planted or captive - please tick it as such when it has become research grade. (please DO NOT tick it before it is research grade, otherwise it cannot be processed in our work flow)
  5. 2c: Look out for duplicates - please add a comment for duplicates: "This is a duplicate of an another observation of yours: please group observations of the same animal/plant at the same place and time in a single observation"
  6. 2d: Look out for multiple species observations: please add a comment for multipules: "Please separate out each species into its own observation. iNaturalist can only cope with one species per observation. On the web version you can use the "Duplicate option on the EditV" button, but please double-check the locality". And add an ID of "State of Matter: Life" if you want.
  7. 2d: Observations without a picture: please add a comment for blanks: "Please sync your app to upload your pictures. if this was a mistake please delete this"

The link to help with these is:
(to avoid us all working on the same page at the same time, replace the "5" on "page=5' with some other number such as "57" - at present there are 166 pages of observations needing identification, but if the page loads as blank, then you have chosen a page number more than there are: choose a smaller number.
((tip: to prevent having to go through the same observations many times, when you finish a page, choose the option "mark all as reviewed". Esp. nearer the end, the same ones will keep on coming up if you dont do this)).

From Tomorrow we will be calling our our experts and more knowledgeable users to change their tack (beginners and higher order helpers can stay on the unidentified observations and clear the last few).
They will start processing the observations that have been identified as "Needs ID" and getting them identified. There will be three levels
** IDs that need confirmation: these will already be identified to species and merely need confirmation. If you are certain of the ID, then please click the "Agree" button. You may also "Agree" tentatively if you know that the person who made the ID is an expert in that group.
** IDs that are wrong: please fix these. Even if it means taking the ID back to genus or family level (or even plants). Add an ID with your best effort, and select the "red" option: 'it is wrong as it is'
** IDs to family or generic level that need species level IDs. Please add the IDs.
or if you dont want to confirm species level IDs, but just work above the species level, then use this rather:

Initially we will just do blanket IDs, but once experts have done a few dozen IDs, they can start "cherry picking" out species that have not yet been identified, and leave the more common species to the more generalist identifiers.
We will coordinate this as we watch our progress.
To help with the finer level IDs, please use this url:
insert your group in the species box (e.g. Birds or Acanthaceae or Lichens - currently it shows Daisies):

If we have time at the very end, we will trawl for false IDs and fix these. But that is more complicated.
And also tackle the Garden Plants needing identification:

Posted on April 29, 2020 08:43 by tonyrebelo tonyrebelo | 5 comments | Leave a comment

April 28, 2020


Well done Cape Town!

At present (9am SAST) the 2020 City Nature Challenge is over except for Hawaii.
The scoreboard at present is:

  1. Cape Town 31.1k
  2. San Franscisco 28.5k
  3. Houston-Galvaston 24.7k


  1. Houston-Galveston 2,764
    2 San Francisco 2,595

  2. Cape Town 2,548
  3. Dallas/Fort Worth 2,231


  1. San Francisco 2,357
  2. Los Angeles 1,495
  3. Washington 1,444 (Cape Town #7: 997)

So very well done all. We posted a formidable target. And even though we were not allowed to leave our homes except for emergencies and shopping, we have recorded a formidable base of species in our gardens and streets across the city.

Time to start identifying! Are you willing and able to help?
Then please look at the following 2 minute turtorial of the Identification tool.

What needs to be done?
To get started, look at the tutorial and click this link

  1. Our first step is to process all observations without any identification at all. The aim is to post them to where our experts can get started working on them.
    So please post to: Birds, Mammals, Reptiles, Amphibians, Lichens, Fungi. Insects & Spiders. BUT PLEASE, do not make an ID of Plants. Leave the plants for those who can recognize the different plant families as our experts work at family level. So if you recognize a Daisy, or Pea, or Grass, or Protea, or Orchid: that is cool make the IDs. Otherwise leave them unidentified.

  2. NOTE: if we all go to this page, then we will all be doing the same thing. So notice in the url (the blue link) that it says "page 5" - please retype the "5" with a number of your choice (below 50) and click the "enter" key. You will then unlikely to be duplicating someone else's IDs.

That is our task for today. Reduce the unknowns and get IDs ready for the experts, specialists and dedicated Capetonians.

1!. if you still have observations to upload, please make that your top priority
2!. If you are an expert in a group, then please feel free to type in your group in the "species" box of the identify page, and start working on those immediately. We will refine the url tomorrow, but today it is a matter of checking the IDs that have been made during the rush and excitement of uploading - and checking that American names have not been incorrectly given to our plants and animals by the AI.

Good luck.
Tomorrow at 11am, we will have a webinar for those with problems or issues. More details later.
Otherwise please feel free to ask questions below.

Posted on April 28, 2020 08:40 by tonyrebelo tonyrebelo | 11 comments | Leave a comment

April 26, 2020


How well are you doing? Have you got your targets yet? You should be about 70-80% of the way now - the last 10% will take all of Monday to get: so time to get at it!

Rain forecast by some, but it wont be more than a splattering in the evening: but perhaps it will get going soon.

Dont forget to look for signs: my Golden Moles started pushing on Saturday: photograph their runnels as evidence.

How to evaluate your progress.

This is mine: it looks complicated but dont worry: just click to open it and then follow instructions:

OK what is this:
It is the compare tool and I am comparing the two filters in the two lines on top.
That gives me two lists - shown in taxonomical order (i.e. frogs, reptiles, birds, mammals, plants etc.)
*** The top line is the filter for my list so far:
notice it gives me the project (city nature challenge) and my name - substitute your iNat name in its place to see your list.
*** The second line is your target list - you probably dont have one: if you do, just put it in here.
If not: let us create one.
open a new tab and inaturalist (mouse-wheel-click on the iNaturalist name on the top menu bar, and click on the new tab that just opened)
Go to the menu bar
cick explore
chose the map tab.
click the eye (Find your location)
click the + and - buttons to zoom in or out
When you have your suburb (or bigger if lots of observations) on the map,
click the orange "Redo search in Map" button.
Let us be a little more sophisticated, and

Go back to your "Compare" tool tab and in the second line (Titled: Autumn Garden) paste the url (Ctrl-P)
if you copied the "?" then remove it it should start "month ..." - if you copied the entire URL, then delete from "http" until the "?"
hit ENTER (or click anywhere else on the page).
Give iNaturalist a few seconds to compile your filters and compare the lists and you are done.
The first column contains the species that you have seen.
the second column contains those that you have dipped out on for the city nature challenge.
Look for the easy species, work out where in your garden/bacony/home these are likely to be (and the time of day best for them) and get to it
Come: on - get our there - we have lots more still to record!!

[[the list may be ridiculous: those species dotn occur in gardens!! and the following filter to the second filter bar:
if you dont have a garden, then rather use

For instance: i get:

Also today: do lichens, under pot plants and inside your compost heap. Also do Ants. Today will probably be better to pollinators, so go stake out your flowerring plants - those with the most activity: remember it will take about 5 minutes after you arrive and dont move around before you are accepted and activity will return to normal

Tomorrow (after the rains) will be better for under logs and stones. And mopping up.
Now is better for insects: the south easter (or north wester, depending on when this front will actually arrive) will reduce insect activity and blow things around, making photography difficult.

Posted on April 26, 2020 10:06 by tonyrebelo tonyrebelo | 0 comments | Leave a comment

April 24, 2020

How does one organize a Lockdown challenge: Activities for the weekend

Without Bioblitzes, Beach walks, Tidal Pool activities, Greenbelt Picnics, hikes, walks, tours, reptile hunts and other fun activities, how should we structure our weekend for the City Nature Challenge?

We all have our own routines now during lockdown, but personally here is my agenda for the City Nature Challenge


  • Birds
  • pollinators - prowling around the flowering plants
  • do easies (chameleon, lizard, bees)

  • midnight start: geckos, moths and snails and slugs (see what has been eating the vegetable seedlings)
  • check bird bath and bird feeders
  • (build a bird feeder or bath if you dont have one)
  • prepare rotten fruit table for flies & beetles
  • prepare checklists


  • Goggo hunt (and any Easter eggs missed)
  • Moths

  • Get sheet and light ready


  • Garden picnic
  • Lichens
  • dawn & dusk: overflying birds
  • Night hunt: eyeshine and spiders

  • evaluate checklist progress and plan
    *make sure Bingo is achieved.

  • Do Polyphagous Borer Beetle survey for atlas
  • Check all Ants done for Ant atlas
    RAIN FORESCAST Evening: not much - Rainfrog Atlas!!!


  • Mopup
  • Going small - compost heap and woodpiles. Lift pots, stones, logs, etc.
  • signs: mole runs, molerat heaps, poops, feathers anything ...

Posted on April 24, 2020 07:05 by tonyrebelo tonyrebelo | 10 comments | Leave a comment

April 22, 2020

Bioblitz Bingo

During the CIty Nature Challenge, how about a little Bingo??
it is simple: fill a row or column of species by posting them on iNaturalist. When you have a completed a row or column on iNaturalist, just tag your kingpiece observation with "Bingo".
Have fun!!

Download it here:

BINGOers here - where are you?:

Posted on April 22, 2020 16:13 by tonyrebelo tonyrebelo | 2 comments | Leave a comment

April 20, 2020

City Checklist!!

Here is a list of the most commonly seen species in Cape Town gardens during autumn over the last few years. Which of these can you observe - and record on iNaturalist?.

Save the list and print it for easy reference.

Posted on April 20, 2020 15:17 by tonyrebelo tonyrebelo | 2 comments | Leave a comment

April 17, 2020

Bioblitzing your Home and Garden

Posted on April 17, 2020 13:31 by tonyrebelo tonyrebelo | 0 comments | Leave a comment